Stars arc around Polaris, at center left in the frame, because of the Earth's rotation during the time the shutter was open. Iridium flares happen fairly frequently because there are lots of Iridium satellites in orbit around the Earth. Flares occur when the angle is just right, and direct sunlight is reflected back to your observing position from surfaces such as antennas or solar panels on the satellite. These flares can get as bright as magnitude minus 8. They can even be seen in the daytime. But they don't last long, only a couple of seconds, so you have to be located in just the right spot on the ground, and you have to be looking at just the right spot in the sky. Heaven's Above is a great web site that will give you predictions for the visibility of all kinds of satellites and Iridium flares when you input the coordinates of your specific observing location. Once you know when and where a flare will occur, it's just a matter of putting the camera on a tripod, focusing it on infinity, and pointing it at the correct area of the sky. Use a wide aperture and ISO 1600. Open the shutter a little bit before the Iridium starts to flare, and then close it when the flare is over. Heaven's Above will tell you where the satellite will first become visible. Although it will start out dim, if you're at a reasonably dark observing site, you should be able to pick it up well before it starts to flare. Open the shutter as soon as you see it, because it won't last that long! In this case, the two Iridium satellites did not flare at exactly the same time. The flares, at magnitude -7 and -8, from Iridium numbers 59 and 96, occurred about 2 minutes apart in time, but very close to the same location in the sky. Leaving the shutter open for 6 minutes captured both of them in a single image. There are also many other satellites that can be seen as they pass overhead in the sky, usually for a period after sunset and before sunrise. At this time,while it is dark on the ground, the satellites are high enough to still be in direct sunlight. Unlike Iridium flares, you will see most satellites maintain a fairly steady brightness until they enter the Earth's shadow, when they will disappear. With a simple camera on a fixed tripod you can photograph bright satellites orbiting the Earth, like the International Space Station, Hubble Space Telescope, and Space Shuttle. Iridium Flare Image Data
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